General Question

Can any old red lightbulb be used as a Safelight?

I want to modify a roll of 35mm film to fit into a 1953 Brownie Holiday that is designed for 127 film. To do this I’m going to have to unroll the film from the cartridge and roll it up so it will fit in the camera. I could do this in a totally dark room by feel, but it would be easier with a little light.

Is a safelight a special kind of red light, or will a red lightbulb from the dollar store work?

those above would be correct—35mm film is sensitive to all wavelengths in the visible light spectrum (though some special types are affected by other parts of the electromagnetic spectrum, like infared light), and thus must not be exposed to any light other than that controlled by an aperture and shutter. Safelights are for black and white photosensitive paper and are not just any red lightbulb (in fact, the light is often yellow or orange), but rather a special type of light manufactured for darkroom use.

Don’t expose film to any kind of light without putting it through development first; red safe lights are only for black and white photo paper (color paper must be exposed and developed in complete darkness as well). The only reason you should expose film to light is if you know how to properly solarize film.

Your only option is to do that in total darkness. Even a safelight, will fog the film. Safelights only work with black-and-white paper. And you would have to get a safelight bulb specifically marketed for use as a safelight. Other red lightbulbs are just way too bright…film must be dealt with in total darkness, until the completion of the fixer bath! unless, of course, you are using a light tight bulk loader or developing tank.